The invention relates to new estra-1,3,5(10)-trien-3-yl sulfamates having a C2-C5 alkyl, alkenyl or alkynyl residue in C13 position and an acyl, oxycarbonyl, aminocarbonyl, sulfonyl, or aminosulfonyl residue on the nitrogen atom of the sulfamate group. The invention is also directed to methods of producing the compounds according to the invention, and to pharmaceutical compositions containing these compounds. The compounds of the invention were found to be steroid sulfatase inhibitors, which exhibit no estrogenic effect.
In the human organism, estrogens are predominantly synthesized and secreted by the ovaries. Accordingly, the estradiol, estrone and estrone sulfate blood levels are subject to fluctuations in sexually mature women during the cycle. During human pregnancy, substantially higher amounts of estrogen are secreted by the placenta compared to the ovary. In addition to these estrogen sources, peripheral estrogen sources play a role in the human organism which, above all, gain importance in those cases where ovarian estrogen secretion has ceased or has not been established yet. As has been demonstrated, these estrogen sources are of major physiological importance in males as well.
Various tissues possess an enzymatic equipment (Purohit A. et al., Regulation of aromatase and sulphatase in breast tumor cells, 150 (1996), p. 65) that causes conversion of adrenal steroids to estrone and estradiol in tissue. Their effect proceeds in an autocrine or paracrine fashion at the site of biosynthesis, and significant estrogen levels do not necessarily have to appear in the blood. Another mechanism by which biologically relevant amounts of estrogen are formed in the tissue is hydrolytic cleavage of estrogen conjugates, particularly estrone sulfate. In this context, the production of estrone in the endometrium and in breast tissue and the tumors proceeding from such tissue is of special pathological importance, because tumor growth can be stimulated in this way. In breast carcinoma, it has been found that the amount of estrogen generated by sulfatase activity (cleavage of estrone sulfate) exceeds that via aromatase by a factor of 50-300 fold (Pasqualini J. R. et al., Estrone sulfatase versus estrone sulfotransferase in human breast cancer: potential clinical applications. J. Steroid Biochem. and Mol. Biol. 69 (1999) 287-292). Similar findings have been gathered by other groups as well. In breast tissue, 10 times more estrone is produced from androstenedione via sulfatase than via aromatase.
Accordingly, the fact can be regarded as proven that sulfatase inhibitors are capable of inhibiting the growth of estrogen-dependent tumors with high efficiency, because they massively reduce the estrogen concentration in the tumor tissue itself.
Under therapeutic aspects, sulfatase inhibitors are therefore the subject of intensified search, which themselves are non-estrogenic and do not yield estrogenic products as a result of hydrolysis. Thus, for example, Purohit A. et al., J. Steroid Biochem. Molec. Biol., Vol. 64, No. 5-6, pp. 269-275 (1998), describe 2-methoxyestrone 3-O-sulfamate to be a potent sulfatase inhibitor that does not exhibit any estrogenic effect on the uterine growth in ovariectomized rats. Estrone 3-O-sulfamates as sulfatase inhibitors have also been described in WO 93/05064. The estrone 3-O-sulfamate with an unsubstituted nitrogen is a strong sulfatase inhibitor (cf., Horwarth et al. in J. Med. Chem. 1994, 37, pp. 219-221, particularly FIG. 3 on page 220). However, this substance also exhibits a strong estrogenic effect, as described by Elger W. et al. in J. Steroid Biochem. Mol. Biol. 55 (1995), pp. 395-403. Other estrone 3-O-sulfamates as sulfatase inhibitors have been disclosed in WO 99/33858. These compounds have no essential estrogenic activity.
Bioorg. and Med. Chem. Lett. 7, 24, 3075-3080 (1997), describes N-acetylestrone 3-O-sulfamate as sulfatase inhibitor. However, this compound has a strong estrogenic effect, exceeding ethynylestradiol with respect to its systemic oral efficacy (cf., WO 97/14712).
Likewise, the DE 197 12 488 A1 describes steroid sulfamates which inhibit steroid sulfatase. The estrogenic effect of these compounds is low or absent. Certain steroid sulfamoyloxy compounds having more than one sulfamate group in their molecules, particularly those which are sulfamoylated in positions characteristic for an estrogenic effect, including substituents or side chains (e.g., in 7 and/or 11 position) which may be located at the periphery of the steroid skeleton, have been described to exhibit a significant increase in sulfatase activity with reduced estrogenic effect. Thus, 3,17-disulfamoyloxy derivatives in particular show good sulfatase activity. According to DE 197 12 488 A1, monosulfamates likewise have good sulfatase inhibition with low estrogenicity, with the exception of A ring sulfamates. As mentioned above, A ring sulfamates are known from WO 97/14712 to be compounds having a distinctly strong estrogenic effect.
It was the object of the present invention to provide additional steroid sulfatase inhibitors which themselves do not exhibit any estrogenic effect and will not yield any estrogenic products as a result of hydrolysis
Surprisingly, it was found that new C13-substituted estra-1,3,5(10)-trien-3-yl sulfamates of general formula I, their physiologically tolerable salts or eaters, 
wherein
R1 represents COR3, COOR4, CONR5R6, SO2R4, SO2NR5R6,
R2 represents hydrogen, C1-C10 alkyl, C1-C10 alkoxyalkyl, C3-C10 cycloalkyl, C2-C10 alkenyl, C2-C10 alkynyl, aryl, aryl (C1-C3)alkyl, or C1-C3 alkylaryl, COR3; COOR4; CONR5R6; SO2R4; SO2NR5R6,
R3 represents H or R4,
R4 represents C1-C17 alkyl, C1-C17 haloalkyl, C2-C17 alkenyl, C2-C17 alkynyl, C3-C10 cycloalkyl, aryl, aryl(C1-C3)alkyl, C1-C3 alkylaryl,
R5, R6 independently represent hydrogen, C1-C5 alkyl, C1-C5 haloalkyl, aryl, aryl(C1-C3)alkyl, C1-C3 alkylaryl, or, together with the nitrogen atom to which they are bound, form a polymethyleneimino residue having 2-6 C atoms or a morpholino residue,
R7, R9 independently represent H, OH, halogen, C1-C5 alkoxy or C1-C5 haloalkoxy,
R8 represents H, OH, C1-C5 alkyl, C1-C5 haloalkyl, C2-C5 alkenyl, C2-C5 alkynyl, or halogen,
R10, R11 represent hydrogen, or R10 and R11 together represent a CH2 group,
R12, R13, R14 independently represent H, OH, C1-C5 alkoxy, or C1-C5 haloalkoxy, or
R12 represents halogen, or
R13 and R14 together represent oxygen, or together represent a xe2x95x90CXY group wherein X and Y independently represent hydrogen, halogen or a C1-C5 alkyl group, or
R13, R14 independently represent C1-C5 alkyl, C2-C5 alkenyl, or C2-C5 alkynyl,
R15 represents C2-C5 alkyl, C2-C5 alkenyl or C2-C5 alkynyl,
R8, R9, R10, R12, R13, R15 independently are in xcex1 or xcex2 position, and
up to 2 additional double bonds may be present in rings B and C, inhibit the activity of steroid sulfatase (EC 3.1.6.2) with extreme efficiency and do not exhibit any estrogenic effect.
In the meaning of the invention, physiologically tolerable salts are alkali or alkaline earth salts, particularly sodium, potassium or ammonium salts.
Conventional, physiologically tolerable inorganic or organic acids which may be esterified with the free hydroxy groups of the compounds of general formula I are e.g. phosphoric acid, sulfuric acid, oxalic acid, maleic acid, fumaric acid, lactic acid, tartaric acid, malic acid, citric acid, salicylic acid, adipic acid, and benzoic acid.
In the meaning of the invention, alkyl represents a branched or unbranched hydrocarbon chain. Accordingly, halozalkyl represents a mono- or polyhalogen-substituted, branched or unbranched hydrocarbon chain. Alkenyl represents a branched or unbranched hydrocarbon chain having at least one double bond. Alkynyl represents a branched or unbranched hydrocarbon chain having at least one triple bond.
Alkoxy represents a branched or unbranched hydrocarbon chain with one or more intervening oxygen atoms. In case of haloalkoxy, the alkoxy residue may be mono- or polysubstituted with halogen.
In the meaning of the invention, aryl represents a phenyl residue which may optionally be substituted, or a heteroaryl residue, e.g. pyridine, picoline, lutidine. collidine, quinoline, acridine, pyridazine, pyrimidine, pyrazine, triazine, pterine, pyrrole, indole, pyrazole, imidazole, 1,2,3-triazole, 1,2,4-triazole, tetrazole, oxazole, thiazole, thiodiazole.
In a particularly preferred embodiment of the invention, R2 represents hydrogen. More preferably, R1 represents an acyl residue, xe2x80x94COR3. In a preferred embodiment, R15 represents ethyl or propyl.
Especially preferred compounds of the invention are the following:
1) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-formyl)-sulfamate
2) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)-sulfamate
3) 17xcex2-Hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
4) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-propionyl)sulfamate
5) 17xcex2-Hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-propionyl)sulfamate
6) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-butyryl)-sulfamate
7) 17xcex1-Hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-butyryl)sulfamate
8) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-valeryl)-sulfamate
9) 17xcex2-Hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-valeryl)sulfamate
10) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl-(N-hexanoyl)-sulfamate
11) 17xcex2-Hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-hexanoyl)sulfamate
12) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-decanoyl)-sulfamate
13) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-stearoyl)-sulfamate
14) 17-Oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-cyclopentanecarbonyl)sulfamate
15) 17-Oxo-14xcex1,15xcex1-methylene-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
16) 17xcex2-Hydroxy-2-methoxy-18a-homo-estra-1,3,5(10)-trien-3-yl [N-(2,2-dimethyl)propionyl]sulfamate
17) 16xcex1-Fluoro-17xcex2-hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
18) 17xcex2-Hydroxy-7xcex1-methyl-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
19) 13-Ethyl-17-hydroxy-18,19-dinor-17xcex1-pregna-1,3,5(10)-trien-20-yn-3-yl (N-acetyl)sulfamate
20) 17xcex2-Methoxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-formyl)sulfamate
21) 17-Oxo-18a-homo-estra-1,3,5(10),8-tetraen-3-yl (N-acetyl)sulfamate
22) 17xcex2-Hydroxy-13-propyl-gona-1,3,5(10)-trien-3-yl (N-acetyl)-sulfamate
23) 17-Oxo-13-propyl-gona-1,3,5(10)-trien-3-yl (N-acetyl)-sulfamate
24) 16xcex1-Fluoro-17-oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
25) 16xcex2-Fluoro-17-oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
26) 16xcex1-Fluoro-17xcex2-hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
27) 16xcex1-Fluoro-17xcex1-hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
28) 16xcex2-Fluoro-17xcex2-hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
29) 16xcex2-Fluoro-17xcex1-hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
30) 2-Methoxy-17-oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
31) 17xcex2-Hydroxy-2-methoxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
32) 2,17xcex2-Dimethoxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
33) 17xcex2-tert-Butoxy-2-methoxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
34) 16xcex1-Fluoro-2-methoxy-17-oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
35) 16xcex1-Fluoro-17xcex2-hydroxy-2-methoxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
36) 2-Ethoxy-17-oxo-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
37) 2-Ethoxy-17xcex2-hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
38) 18a-Homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
39) 17-Methylene-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
40) 17-Difluoromethylene-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
41) 17-Ethylidene-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
42) 17-Oxo-18a-homo-13xcex1-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
43) 17xcex2-Hydroxy-18a-homo-13xcex1-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
44) 17-Oxo-18a-homo-13xcex1-estra-1,3,5(10),8-tetraen-3-yl (N-acetyl)sulfamate
45) 17-Oxo-18a-homo-estra-1,3,5(10),6,8-pentaen-3-yl (N-acetyl)sulfamate
46) 17-Oxo-18a-homo-estra-1,3,5(10),7-tetraen-3-yl (N-acetyl)sulfamate
47) 17-Oxo-18a-homo-estra-1,3,5(10),8(14)-tetraen-3-yl (N-acetyl)sulfamate
48) 17xcex2-Hydroxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-trifluoroacetyl)sulfamate
49) 17-Oxo-18a-homo-1,3,5(10)-trien-3-yl (N-nonafluorovaleroyl)sulfamate
50) 17-Oxo-2-trifluoromethoxy-18a-homo-estra-1,3,5(10)-trien-3-yl (N-acetyl)sulfamate
Surprisingly, replacement of the C13 methyl group which is characteristic for estra-1,3,5(10)-triene derivatives by a C2-C5 alkyl group in 13 position, which optionally may include double or triple bonds, results in complete disappearance of the estrogenic effect without impairing the sulfatase-inhibiting activity of the compounds.
The strong sulfatase-inhibiting activity of the compounds according to the invention becomes manifest in a reduced cleavage of estrone sulfate in organs and tissues of ovariectomized rats. Another characteristic is that the ratio of toluene-extractable metabolites of estrone sulfate in the blood is massively reduced. Therefore, the action pattern of the compounds according to the invention allows their use in the production of drugs for the treatment of estrogen-dependent diseases, namely, for all those therapies where the sulfatase activity is to be inhibited and an estrogenic side effect is undesirable. The treatment of estrogen-dependent tumor diseases may be mentioned as an example.
Therefore, the present invention is also directed to pharmaceutical compositions containing at least one compound of general formula I, optionally together with pharmaceutically tolerable adjuvants and/or vehicles.
Such pharmaceutical compositions and drugs can be used in oral, rectal, vaginal, subcutaneous, percutaneous, intravenous, or intramuscular applications. In addition to conventional vehicles and/or diluents, they contain at least one compound of general formula I.
The drugs of the invention are produced in a well-known fashion using conventional solid or liquid vehicles or diluents and conventionally employed pharmaceutic-technical adjuvants, with a suitable dosage as appropriate for the desired type of application. Preferred formulations consist of an administration form which is suitable for oral application. For example, such administration forms are tablets, film tablets, coated tablets, capsules, pills, powders, solutions or suspensions, or depot forms as well.
Obviously, parenteral formulations such as injection solutions are also possible. Furthermore, suppositories and agents for vaginal application may also be mentioned, for example.
For example, appropriate tablets can be obtained by mixing the active substance with well-known adjuvants, e.g. inert diluents such as dextrose, sugar, sorbitol, mannitol, polyvinylpyrrolidone, disintegrants such as corn starch or alginic acid, binders such as starch or gelatin, lubricants such as magnesium stearate or talc, and/or agents to achieve a depot effect, such as carboxypolymethylene, carboxymethylcellulose, cellulose acetate phthalate, or polyvinyl acetate. The tablets may also be made up of several layers.
Similarly, coated tablets can be produced by coating cores prepared in an analogous fashion as tablets, using agents conventionally employed in tablet coatings, e.g. polyvinylpyrrolidone or shellac, gum arabic, talc, titanium oxide, or sugar. The coating may also consist of multiple layers, where the adjuvants mentioned above in context with the tablets can be used.
Solutions or suspensions including the compounds of the invention of general formula I may additionally contain taste-improving agents such as saccharine, cyclamate or sugars, as well as e.g. flavors, such as vanillin or orange extract. In addition, they may contain suspending aids such as sodium carboxymethylcellulose, or preservatives such as p-hydroxybenzoates.
For example, capsules containing the compounds of general formula I can be produced by mixing the compound(s) of general formula I with an inert vehicle such as lactose or sorbitol and encapsulating in gelatin capsules.
For example, suitable suppositories can be produced by admixing vehicles intended for such purpose, such as neutral fats or polyethyleneglycol or derivatives thereof.
Suitable dosages of the compounds according to the invention are from 0.001 to 10 mg per day, depending on body weight, age and constitution of the patient, and the required daily dose may be applied via single or multiple administrations.
The invention is also directed to a method of producing the compounds of the invention of general formula I 
wherein the residues R1 through R15 have the above-specified meanings,
in which method
a) suitable estra-1,3,5(10)-trien-3-yl sulfamate derivatives having residues R2 and R7 through R15 as indicated above, which have at least one hydrogen atom on the nitrogen atom of the sulfamate residue, are reacted with a suitable activated carboxylic acid, sulfonic acid or amidosulfonic acid, or a suitable activated carbonic acid monoester or carbonic acid monoamide or
b) suitable 3-hydroxy-estra-1,3,5 (10)-triene derivatives having residues R7 through R15 as indicated above are reacted with an activated (Nxe2x80x94COR3)amidosulfonic acid, (Nxe2x80x94COOR4)amidosulfonic acid, (Nxe2x80x94CONR5R6)amidosulfonic acid, (Nxe2x80x94SO2R4)amidosulfonic acid, or (Nxe2x80x94SO2NR5R6)amidosulfonic acid,
in a per se known fashion, optionally in the presence of a base each time, the products thus obtained are optionally reacted further in a suitable manner, and the products thus obtained are optionally converted to physiologically tolerable metal salts or esters.
The 3-hydroxy-estra-1,3,5(10)-triene derivatives having residues R7 through R15 are prepared according to methods common in steroid chemistry, such as exemplified in Liebigs Ann. Chem. 702 (1967), 141-148. Estra-1,3,5(10)-trien-3-yl sulfamate derivatives having residues R2 and R7 through R15 can be provided in analogy to methods exemplified in Steroids 61 (1996), 710-717.